I agree with other replies-it sounds like your shirt tails maybe too short. However, you are stuck with the shirts already in your possession; and to keep them from riding up, you can use garder straps that attach to your socks and the other end to your shirt tails. I used to buy them at the PX in the service. We used them for honor guard detail with our class A (dress) uniforms. This little item worked very well, however, it is a pain in the rear end to put them on every day. Your shirts will look perfectly "tucked" into your pants and will not "ride up." So, for your next batch of shirts, try something a little bit longer, but for your current shirts, take a look for these garder straps-or whatever they are called. Check the internet-you will find them. I hope this helps.